The most common and most likely answer to this crossword clue is the 6 letter word NADIRS
I've seen this crossword clue in Financial Times
N
A
D
I
R
S
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The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does NADIRS mean?
NADIRS noun- The point of the celestial sphere, directly opposite the zenith; inferior pole of the horizon; point of the celestial sphere directly under the place of observation.
- The lowest point; time of greatest depression.
- The axis of a projected conical shadow; the direction of the force of gravity at a location; down.
- An empty box added beneath a full one in a beehive to give the colony more room to expand or store honey.
- To extend (a beehive) by adding an empty box at the base.